The present invention relates to copyright protection of digital data.
Software copyright protection is a central concern in software development, and in copyright law itself. Typically, software is distributed in shrink-wrap packages containing diskettes and/or CD-ROMs, and over the Internet via ftp servers. Protecting software from rampant unauthorized copying, distribution and use (xe2x80x9csoftware piracyxe2x80x9d) is one of the most challenging problems facing the software industry.
Over the past years, several techniques have been developed for combating software piracy. These include use of hardware plugs, use of license keys, use of tokens and sophisticated encryption systems.
One of the leading technologies for controlling use of software within turnkey transaction systems is the Digital Rights Management system of InterTrust(copyright) Technologies Corp. of Sunnyvale, Calif., as described in U.S. Pat. Nos. 5,892,900, 5,410,598, 5,050,213, 4,977,594 and 4,827,508. Information about InterTrust is available on the web at http://www.intertrust.com.
Another such leading technology is the CyberSales Solution(trademark) of SoftLock.com, Inc. of Maynard, Mass., as described in U.S. Pat. No. 5,509,070. CyberSales Solution provides locking and unlocking functionality so that content can be securely previewed by consumers, electronically purchased and redistributed, and it protects the content in an initial transaction and in subsequent information pass-along. Content providers can control how much information is available without paying, and disable, or additionally charge for, the ability to print or cut and paste. CyberSales Solution handles secure transactions, remittance processing, reports, audits and customer service. Information about CyberSales Solution is available on the web at http://www.softlock.com.
With the advent of the use of compelling multi-media on web pages accessible over the Internet, protection of digital images and other media is becoming increasingly critical. Web designers are reluctant to use valuable digital xe2x80x9cworks of artxe2x80x9d knowing that users can easily copy them onto their own computers, and use them for their own unauthorized purposes. Moreover, anyone using a web browser to view an image posted on the Internet can easily copy the image by simply positioning a mouse pointer over the displayed image, clicking on the right mouse button and selecting a xe2x80x9cSave Image As . . . xe2x80x9d command. Copyright and piracy issues are major problems for web publishers.
Prior art techniques for protecting digital images include the embedding of invisible digital watermarks within images, so that copies of protected images can be traced. Digimarc Corporation of Lake Oswego, Oreg. embeds hidden messages within pixel data for identifying protected images, and tracks their distribution over the Internet to monitor potential copyright infringement. Digimarc images carry unique IDs that link to pre-determined locations on the web. Digimarc images are compatible with standard image formats, such as JPEG, and can be opened and displayed by standard image readers. However, when opened with a Digimarc reader, the images are displayed together with a xe2x80x9cWeb look upxe2x80x9d button that enables a user to identify the sources of the images. Digimarc technology is described in U.S. Pat. Nos. 5,862,260, 5,850,481, 5,841,978, 5,841,886, 5,832,119, 5,822,436, 5,809,160, 5,768,426, 5,765,152, 5,748,783, 5,748,763, 5,745,604, 5,721,788, 5,710,834 and 5,636,292. Information about Digimarc is available on the web at http://www.digimarc.com.
These techniques are useful in thwarting digital image piracy to the extent that they trace pirated content, but they do not prevent unauthorized copying of digital images in the first place.
Other prior art techniques require a webmaster to modify images residing on a server computer in order to protect them. The webmaster is also required to modify his web pages accordingly, so as to reference the modified images. SafeMedia(trademark) is a software product of Internet Expression, Inc. of Exton, Pa. that converts images from a standard format such as JPEG into SIF (Safe Image Format). SIF images can only be viewed with a SafeMedia Java viewer. SafeMedia embeds a host or domain name into an image, and checks that the image is located on the web site it was intended for. SafeMedia also includes enhanced system control for preventing screen capture by disabling a clipboard. Information about SafeMedia is available on the web at http://www.safemedia.com.
These techniques are difficult to embrace, since they require modification of all protected images on the web, as well as modification of the web pages that reference them. Furthermore the SIF Java viewer has the limitation of only being able to load images from the same server that the viewer came from.
Other prior art techniques for protecting digital images use Java applets within web browsers to disable the menu that pops up when a user right clicks on a displayed image within his web browser. Copysight(copyright) is a software application of Intellectual Protocols, LLC of Nanuet, N.Y. that uses digital watermarking and fingerprinting to protect images, and includes a Java applet that disables the ability to save displayed images within a web browser and the ability to print them. Copysight operates by converting unprotected files to protected files that are encrypted and that contain digital fingerprints. Copysight also tracks distribution of protected images across the Internet, and issues reports of potential copyright infringement. It allows a web administrator to select which files are to be protected. Information about Copysight is available on the web at http://www.ip2.com.
These techniques disable unauthorized copying of digital images from within web browsers, but they do not protect the images from being copied by an application external to the web browser. For example, they do not prevent a user from copying digital images displayed in his web browser by means of an application running external to the web browser, such as an image editing tool, or by means of a Print Screen or other such command that serves to copy contents of a video buffer to a clipboard. Thus a Java applet that prevents unauthorized copying of digital images from within Netscape Communicator or Internet Explorer can be circumvented by a user pressing on a Print Screen button of his keyboard, or by a user copying and pasting from a window of his web browser to a window of another software application.
The present invention provides a method and system for enabling a user to view protected image data using his web browser without being able to copy it. The slogan xe2x80x9cLook but Don""t Touch(trademark)xe2x80x9d has been adopted to describe the feature of the present invention that enables a user to view content without being able to copy it into his computer.
The present invention is distinct from prior art methods in several respects. A first distinction is that the present invention displays an image to a user without downloading unmodified image data to the user""s computer. Thus, unlike software piracy techniques that protect an original copy of software from being illegally copied, the present invention does not provide an original copy in the first place.
A second distinction is that the present invention prevents a user from copying a protected image both from within and from without his web browser. Specifically, the present invention blocks copying of an image from within his web browser, when a user selects the xe2x80x9cSave Image As . . . xe2x80x9d command and when a user prints the contents of a web browser window. It also blocks copying of an image from without when a user presses the xe2x80x9cPrint Screenxe2x80x9d button of his keyboard or attempts to copy from his web browser window and paste onto a window of another application, or when a third party software application attempts to use the xe2x80x9cPrint Screenxe2x80x9d command.
In a preferred embodiment, the present invention uses a software web server plug-in that filters HTTP requests and sends substitute data, such as encrypted image data, for requested image data that is protected. It also uses a software web browser plug-in for displaying the substitute data and for blocking the ability to copy protected image data being displayed from the video buffer of the user""s computer. It also uses a management tool for setting protection status of images and web pages residing on one or more server computers.
There is thus provided in accordance with a preferred embodiment of the present invention a method for protecting digital images distributed over a network, including the steps of receiving a request from a client computer running a network browser, for an original layout page containing references to digital images therein, parsing the original layout page for the references to digital images, generating a modified layout page from the original layout page by replacing at least one of the references to digital images in the original layout page with references to substitute data, and sending the modified layout page to the client computer.
There is further provided in accordance with a preferred embodiment of the present invention a method for protecting files distributed over a network, including the steps of displaying a list of files, generating protection status information in response to selection by a user of at least one of the files in the list of files, and sending the protection status information to a server computer.
There is yet further provided in accordance with a preferred embodiment of the present invention a system for protecting digital images distributed over a network, including a receiver receiving a request from a client computer running a network browser, for an original layout page containing references to digital images therein, a layout page parser parsing the original layout page for the references to digital images, a layout page generator generating a modified layout page from the original layout page by replacing at least one of the references to digital images in the original layout page with references to substitute data, and a transmitter sending the modified layout page to the client computer.
There is moreover provided in accordance with a preferred embodiment of the present invention a system for protecting files distributed over a network, including a user interface displaying a list of files, a protection status manager generating protection status information in response to selection by a user of at least one of the files in the list of files, and a transmitter sending the protection status information to a server computer.
There is additionally provided in accordance with a preferred embodiment of the present invention a method for protecting digital images distributed over a network, including the steps of receiving a request from a client computer, submitting the request to a server computer, receiving an original layout page containing references to digital images therein from the server computer, parsing the original layout page for the references to digital images, generating a modified layout page from the original layout page by replacing at least one of the references to digital images in the original layout page with references to substitute data, and sending the modified layout page to the client computer.
There is further provided in accordance with a preferred embodiment of the present invention a system for protecting digital images distributed over a network, including a receiver receiving a request from a client computer and receiving an original layout page containing references to digital images therein from a server computer, a transmitter submitting the request to the server computer and sending a modified layout page to the client computer, a layout page parser parsing the original layout page for the references to digital images, and a layout page generator generating the modified layout page from the original layout page by replacing at least one of the references to digital images in the original layout page with references to substitute data.
There is yet further provided in accordance with a preferred embodiment of the present invention a method for protecting digital images displayed in a web browser, including the steps of displaying a digital image by a web browser, the digital image including pixel data, requesting access to pixel data of the digital image, and in response to the requesting, blocking access to pixel data of the digital image.
There is additionally provided in accordance with a preferred embodiment of the present invention a method for protecting digital images displayed in a web browser, including the steps of displaying a digital image by a web browser, the digital image including pixel data, requesting access to pixel data of the digital image, in response to the requesting, intercepting a request to access pixel data of the digital image, and providing substitute data to pixel data of the digital image in a response to the request to access pixel data of the digital image.
There is moreover provided in accordance with a preferred embodiment of the present invention a system for protecting digital images displayed in a web browser, including a web browser displaying a digital image, the digital image including pixel data, a command processor requesting access to pixel data of the digital image, and a request blocker, blocking access to pixel data of the digital image requested by the command processor.
There is further provided in accordance with a preferred embodiment of the present invention a system for protecting digital images displayed in a web browser, including a web browser displaying a digital image, the digital image including pixel data, a command processor requesting access to pixel data of the digital image, a request interceptor intercepting a request to access pixel data of the digital image received from the command processor, and a data processor providing substitute data to pixel data of the digital image in a response to the request to access pixel data of the digital image.